Long noncoding RNA CASC7 inhibits the proliferation and migration of papillary thyroid cancer cells by inhibiting miR-34a-5p

Dual roles of long non-coding RNAs in thyroid cancer: regulation of programmed cell death pathways

Thyroid cancer (TC) represents the most common endocrine malignancy; however, the intricacies of its carcinogenesis pose significant challenges to therapeutic interventions. A comprehensive understanding of the molecular mechanisms that drive TC progression is crucial for the development of effective treatment strategies, especially considering the increasingly recognized role of non-coding RNAs (ncRNAs) in oncogenesis. Notwithstanding recent advancements, the regulatory functions of long non-coding RNAs (lncRNAs) and their interactions with microRNAs (miRNAs) in the context of TC are not yet fully elucidated. This review aims to address this knowledge deficiency by investigating the dual roles of lncRNAs in the pathogenesis of TC, specifically their regulation of programmed cell death (PCD) pathways. Current literature indicates that disrupted competitive endogenous RNA (ceRNA) networks are involved in drug resistance, epithelial-mesenchymal transition (EMT), as well as tumor proliferation, angiogenesis, invasion, and metastasis in TC. The basis of cancer therapy-induced tumor cell elimination is programmed cell death (PCD), which includes well-studied processes such as apoptosis, autophagy, and ferroptosis as well as novel pathways, such as cuproptosis, immunogenic cell death (ICD), and PANoptosis. Recent research has shown the critical function of long non-coding RNAs (lncRNAs) in modifying these several PCD pathways, impacting TC growth and therapy response. This review synthesizes evidence on how lncRNAs regulate PCD to influence TC progression and therapeutic outcomes. Additionally, we examine the clinical relevance of lncRNAs in TC, highlighting their potential as biomarkers for diagnosis and prognosis, therapeutic targets, and contributors to drug resistance, while emphasizing recent advancements in this field.

The role of MiRNA-34 family in different signaling pathways and its therapeutic options

MiRNAs are short non-coding RNA molecules that have been shown to affect a vast number of genes at the post-transcriptional level, hence regulating several signaling pathways. Because the miRNA-34 family regulates a number of different signaling pathways, including those linked to cancer, the immune system, metabolism, cellular structure, and neurological disorders, it has garnered a great deal of attention from researchers. Members of the miRNA-34 family have been shown to inhibit tumors in a variety of cancer types. This family is also important for obesity, the cardiovascular system, and glycolysis. It's interesting to note that the miRNA-34 family is known to play a role in major depressive disorder, schizophrenia, Parkinson's disease (PD), adverse childhood experiences or trauma, regulation of stress responses, Alzheimer's disease (AD), and stress-related psychatric conditions. In this review, the expected targets of the miRNA-34 family are presented alongside the well-established targets identified by pathway analysis. Furthermore, the therapeutic potential of this miRNA family will be discussed.

Non-coding RNAs in the pathophysiology of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is the largest unmet clinical need in cardiovascular medicine. Despite decades of research, the treatment option for HFpEF is still limited, indicating our ongoing incomplete understanding on the underlying molecular mechanisms. Non-coding RNAs, comprising of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), are non-protein coding RNA transcripts, which are implicated in various cardiovascular diseases. However, their role in the pathogenesis of HFpEF is unknown. Here, we discuss the role of miRNAs, lncRNAs and circRNAs that are involved in the pathophysiology of HFpEF, namely microvascular dysfunction, inflammation, diastolic dysfunction and cardiac fibrosis. We interrogated clinical evidence and dissected the molecular mechanisms of the ncRNAs by looking at the relevant in vivo and in vitro models that mimic the co-morbidities in patients with HFpEF. Finally, we discuss the potential of ncRNAs as biomarkers and potential novel therapeutic targets for future HFpEF treatment.

MiR-146b-5p regulates the scavenging effect of GPx-3 on peroxide in papillary thyroid cancer cells

Background

Glutathione peroxidase (GPx) is an important antioxidant enzyme in thyroid follicular cells. Reduced levels of glutathione peroxidase 3 (GPx-3) expression in papillary thyroid cancer (PTC) are associated with poor prognosis. However, the reason for the decreased expression level of GPx-3 in PTC is unclear.

Methods

The expression of GPx-3 in papillary thyroid carcinoma and adjacent normal tissue (n = 18) was detected by Western blotting. Bioinformatics was used to predict the relationship between the level of GPx-3 and gender, age, lymph node metastasis, stage, BRAFV600E mutation, and recurrence-free survival of patients. The possible upstream microRNAs of GPx-3 were analyzed by bioinformatics tools also. We verified the relationship between GPx-3 and upstream microRNA by dual luciferase reporter assay and enzyme-linked immunosorbent assay (ELISA).

Results

The protein level of GPx-3 decreased in PTC, and analysis of public database datasets suggests that its decreased expression may be associated with the BRAFV600E mutation. MiR-146b-5p was significantly overexpressed in PTC. The dual luciferase reporter assay verified the effect of miR-146b-5p on 3'-UTR of GPx-3 mRNA. Knockdown of miR-146b-5p in thyroid cancer cell lines TPC-1 and BCPAP increased GPx-3 expression levels, accompanied by an increase in the conversion of glutathione (GSH) to oxidized glutathione (GSSG).

Conclusions

In conclusion, the level of GPx-3 decreases in papillary thyroid carcinoma and impairs intracellular peroxide clearance, due to the inhibitory effect of miR-146b-5p. The accumulation of intracellular peroxides may contribute to the poor prognosis of thyroid cancer.

Identifying and analyzing the key genes shared by papillary thyroid carcinoma and Hashimoto's thyroiditis using bioinformatics methods

Background

Hashimoto's thyroiditis (HT) is a chronic autoimmune disease that poses a risk factor for papillary thyroid carcinoma (PTC). The present study aimed to identify the key genes shared by HT and PTC for advancing the current understanding of their shared pathogenesis and molecular mechanisms.

Methods

HT- and PTC-related datasets (GSE138198 and GSE33630, respectively) were retrieved from the Gene Expression Omnibus (GEO) database. Genes significantly related to the PTC phenotype were identified using weighted gene co-expression network analysis (WGCNA). Differentially expressed genes (DEGs) were identified between PTC and healthy samples from GSE33630, and between HT and normal samples from GSE138198. Subsequently, functional enrichment analysis was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Transcription factors and miRNAs regulating the common genes in PTC and HT were forecasted using the Harmonizome and miRWalk databases, respectively, and drugs targeting these genes were investigated using the Drug-Gene Interaction Database (DGIdb). The key genes in both GSE138198 and GSE33630 were further identified via Receiver Operating Characteristic (ROC) analysis. The expression of key genes was verified in external validation set and clinical samples using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC).

Results

In total, 690 and 1945 DEGs were associated with PTC and HT, respectively; of these, 56 were shared and exhibited excellent predictive accuracy in the GSE138198 and GSE33630 cohorts. Notably, four genes, Alcohol Dehydrogenase 1B (ADH1B), Active BCR-related (ABR), alpha-1 antitrypsin (SERPINA1), and lysophosphatidic acid receptor 5 (LPAR5) were recognized as key genes shared by HT and PTC. Subsequently, EGR1 was identified as a common transcription factor regulating ABR, SERPINA1, and LPAR5 expression. These findings were confirmed using qRT-PCR and immunohistochemical analysis.

Conclusion

Four (ADH1B, ABR, SERPINA1, and LPAR5) out of 56 common genes exhibited diagnostic potential in HT and PTC. Notably, this study, for the first time, defined the close relationship between ABR and HT/PTC progression. Overall, this study provides a basis for understanding the shared pathogenesis and underlying molecular mechanisms of HT and PTC, which might help improve patient diagnosis and prognosis.

Non-coding RNA-based therapeutics in cancer therapy: An emphasis on Wnt/β-catenin control

Non-coding RNA transcripts are RNA molecules that have mainly regulatory functions and they do not encode proteins. microRNAs (miRNAs), lncRNAs and circRNAs are major types of this family and these epigenetic factors participate in disease pathogenesis, especially cancer that their abnormal expression may lead to cancer progression. miRNAs and lncRNAs possess a linear structure, whereas circRNAs possess ring structures and high stability. Wnt/β-catenin is an important factor in cancer with oncogenic function and it can increase growth, invasion and therapy resistance in tumors. Wnt upregulation occurs upon transfer of β-catenin to nucleus. Interaction of ncRNAs with Wnt/β-catenin signaling can determine tumorigenesis. Wnt upregulation is observed in cancers and miRNAs are able to bind to 3'-UTR of Wnt to reduce its level. LncRNAs can directly/indirectly regulate Wnt and in indirect manner, lncRNAs sponge miRNAs. CircRNAs are new emerging regulators of Wnt and by its stimulation, they increase tumor progression. CircRNA/miRNA axis can affect Wnt and carcinogenesis. Overall, interaction of ncRNAs with Wnt can determine proliferation rate, migration ability and therapy response of cancers. Furthermore, ncRNA/Wnt/β-catenin axis can be utilized as biomarker in cancer and for prognostic applications in patients.

MicroRNAs as the critical regulators of cell migration and invasion in thyroid cancer

Thyroid cancer (TC) is one of the most frequent endocrine malignancies that is more common among females. Tumor recurrence is one of the most important clinical manifestations in differentiated TC which is associated with different factors including age, tumor size, and histological features. Various molecular processes such as genetic or epigenetic modifications and non-coding RNAs are also involved in TC progression and metastasis. The epithelial-to-mesenchymal transition (EMT) is an important biological process during tumor invasion and migration that affects the initiation and transformation of early-stage tumors into invasive malignancies. A combination of transcription factors, growth factors, signaling pathways, and epigenetic regulations affect the thyroid cell migration and EMT process. MicroRNAs (miRNAs) are important molecular factors involved in tumor metastasis by regulation of EMT-activating signaling pathways. Various miRNAs are involved in the signaling pathways associated with TC metastasis which can be used as diagnostic and therapeutic biomarkers. Since, the miRNAs are sensitive, specific, and non-invasive, they can be suggested as efficient and optimal biomarkers of tumor invasion and metastasis. In the present review, we have summarized all of the miRNAs which have been significantly involved in thyroid tumor cells migration and invasion. We also categorized all of the reported miRNAs based on their cellular processes to clarify the molecular role of miRNAs during thyroid tumor cell migration and invasion. This review paves the way of introducing a non-invasive diagnostic and prognostic panel of miRNAs in aggressive and metastatic TC patients.

CASC7: a LncRNA with potential clinical application

AIM

To explore the novel lncRNA CASC7 and its potential clinical applications.Long non-coding RNAs (IncRNAs) are defined as non-coding genes with a length exceeding 200 nt. As transcripts of RNA polymerase Il, they have limited coding potential due to the lack of an open reading frame in the gene segment. Research has confirmed that lncRNAs are important biological factors that regulate many life processes in the human body through different mechanisms. This work focused on Cancer Susceptibility Candidate 7 (CASC7), a lncRNA with nuclear and cytoplasmic localization. Publicly available databases show that CASC7 is differentially expressed in human organs as well as in tumor tissues. A study confirmed that CASC7 is abnormally expressed in colorectal cancer, glioma, breast cancer, non-small cell lung cancer and thyroid cancer. In male infertility, asthma and heart failure, it may also be a potential therapeutic target and promising biomarker. CASC7 mainly plays a biological effect through direct or indirect effects of promoting or inhibiting the expression of related genes. Currently, only few studies have assessed CASC7, and its mechanisms are not clear. The main purpose of this review was to examine CASC7 and its possible molecular mechanisms and clinical significance in cancer.

CONCLUSION

We reviewed the recent research progress of CASC7 and its potential as a diagnostic marker and therapeutic target, and provide an outlook on its future application in terms of mechanism.Key points:CASC7 is a novel lncRNA, for which there are few reports.Aberrant expression of CASC7 may be associated with the emergence and treatment of many clinical diseases, including malignancy.

Long non-coding RNA CASC7 suppresses malignant behaviors of breast cancer by regulating miR-21-5p/FASLG axis

Recently, it has been increasingly proved that lncRNAs are functionally involved in a majority of tumor progression. LncRNA CASC7 has also been revealed to participate in the development of several cancers as a tumor promoter or suppressor. Herein, we focus on uncovering the role and underlying molecular mechanism of CASC7 in breast cancer. Tumor tissues and the paired paracancerous tissues from the breast cancer patients were used to evaluate the level of CASC7 in breast cancer. By analyzing the CASC7 expression in breast cancer cell lines, both the expression levels of CASC7 in cancer tissues and cell lines were obviously downregulated compared to those in paired paracancerous tissues and normal human epithelial MCF10A cells. Subsequently, the construction of lentivirus overexpression system (oe-CASC7 and oe-NC) was used to elevate the expression of CASC7. A series of functional experiments were conducted to show that the cell proliferation, migration, and invasion were inhibited when CASC7 overexpressed in breast cancer cells. Meanwhile, the apoptosis of oe-CASC7 cells was induced compared to the oe-NC breast cancer cells. We further confirmed that CASC7 functions by regulating miR-21-5p/FASLG axis. Finally, a xenograft model in nude mice verified that CASC7 was a tumor suppressor in breast cancer. These results suggest that lncRNA CASC7 suppresses to malignant behaviors of breast cancer by modulating miR-21-5p/FASLG axis. Abbreviations lncRNAs: long non-coding RNAs; ceRNA: competing endogenous RNA; CASC7: cancer susceptibility candidate 7; miRNAs: MicroRNAs; MAPK10: mitogen-activated protein kinase 10; FASLG: Tumor Necrosis Factor Ligand Superfamily Member 6; FAS: Tumor Necrosis Factor Receptor Superfamily Member 6.